locl

I'm making a big multilingual sans serif and by default, the "a" and the "g" are double storey. I do include the single story versions available by "salt" because this feature works virtually everywhere, where there is Opentype).

However, I've heard that the Germans mostly use the single story g. I've searched pictures of various street signs in Germany and Austria and I haven't found any double story g's.

Would it be ok to include 'locl' feature for German language to substitute only the g (while leaving the "a" double story)? I do understand that the single story g has its roots in Fraktur. And is it a German-only preference or the neighbour languages like Dutch, Danish, Swedish, etc. look more natural with a single storey g?

Some languages have problems with f-ligatures. One example is German, where ligatures across Wortfugen can be a source of confusion; another is Turkish, in which the dotless ı requires special treatment.

Have there been any efforts to identify (and compile a list of) such problems, and is it considered good practice to code those exceptions as language-specific OpenType alternates? Say, "ligatures for dflt, no ligatures for german"? Or would that go against users' expecations? How well are such features implemented in software at all?

Another solution, of course, is a Linotype ("Sabon") f, but you know, I do have a thing for nice fi and fl ligatures :)